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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Temporal dynamics of resistance in an exotic plant Solidago altissima: geographic variation of plant-herbivore interactions in native and invaded range / 外来植物セイタカアワダチソウの抵抗性の時間的な動態:原産地と侵入地における植物-植食者相互作用の地理的変異

Sakata, Yuzu 23 March 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19529号 / 理博第4189号 / 新制||理||1601(附属図書館) / 32565 / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 大串 隆之, 教授 中野 伸一, 教授 曽田 貞滋 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
22

Intraspezifische Variabilität und Einflüsse von Anbaumaßnahmen auf den Inhaltsstoffgehalt und Ertrag von Solidago virgaurea L.

Lück, Lorna 03 August 2001 (has links)
Mit den vorgestellten Untersuchungen sollten das Potential der in Europa vorkommenden Echten Goldrute für den Anbau evaluiert und der Einfluß von Erntetermin, Schnitthöhe und Düngungsmaßnahmen sowie der abiotischen Umweltfaktoren Licht und Wasser auf den Ertrag und den Inhaltsstoffgehalt von Solidago virgaurea L. geprüft werden. In vier Feldversuchen wurden Inhaltsstoffgehalte, Ertragsparameter, Entwicklungsstadien sowie morphologische Merkmale untersucht. Die Gehalte an Flavonolglycosiden, Phenolglucosiden und Kaffeesäurederivaten wurden mittels HPLC und nachfolgender DAD-Detektion bestimmt. 45 Akzessionen aus dem europäischen Verbreitungsgebiet wurden anhand ihres Blühtermines gegliedert, den Unterarten virgaurea und minuta zugeordnet, und mit Hilfe von 33 morphologischen Merkmalen charakterisiert. Die Analyse von 452 Einzelpflanzen ergab Spannweiten von 0.4 bis 2.4 % Flavonolglycosiden, 0.7 bis 4.6 % Kaffeesäurederivaten und 0 bis 1.6 % Phenolglucosiden. Die phytochemische Zusammensetzung war innerhalb der einzelnen Akzessionen, insbesondere in der Unterart virgaurea hoch variabel. In einer anbaubezogenen Gesamtbewertung der Akzessionen erwiesen sich Herkünfte der Unterart virgaurea aufgrund hoher Drogenerträge von maximal 109 dt/ha und eines ausgewogenen Inhaltsstoffspektrums als die Wertvollsten. Im Lauf der Ontogenese stieg der Drogenertrag der Echten Goldrute an, während die Inhaltsstoffgehalte schwankten (Kaffeesäurederivate, Flavonolglycoside) oder relativ kontinuierlich absanken (Phenolglucoside). Eine gehaltsorientierte Ernte müßte daher zum relativ frühen Zeitpunkt des mittleren Knospenstadiums erfolgen. Hohe Masse- und Inhaltsstofferträge sind in einem Ernteverfahren mit niedrigen Schnitthöhen von 15 bis 30 cm erreichbar. In voll besonnten Pflanzen wurde im Vergleich zu schattierten eine höhere Anreicherung von Flavonolglycosiden und Kaffeesäurederivaten festgestellt, die durch die UV-Schutzfunktion dieser Stoffgruppen erklärbar ist. Daher muß angenommen werden, daß ontogenetisch bedingte Gehaltsveränderungen der Flavonolglycoside und Kaffeesäurederivate durch unterschiedliche Strahlungsverhältnisse überlagert werden können. Stickstoffdüngung verursachte neben der erwarteten ertragssteigernden Wirkung Unterschiede im Inhaltsstoffgehalt. In der ungedüngten Variante wurden jeweils die höchsten Flavonolglycosidgehalte bestimmt, gefolgt von der organischen Düngung sowie der Mehrnährstoff- und Stickstoffdüngung. Während die ermittelten Stickstoff- (maximal 96 kg/ha N) und Phosphorentzüge (maximal 39 kg/ha P2O5) vergleichsweise gering waren, wurden Kaliumentzüge (maximal 172 kg/ha K2O) festgestellt, die auch im Vergleich zu anderen Blatt- und Krautdrogen relativ hoch ausfielen. Im Gesamtüberblick aller Einflüsse wurde deutlich, daß Flavonolglycoside, gefolgt von Kaffeesäurederivaten am empfindlichsten auf Umwelteinflüsse wie Lichteinstrahlung und Nährstoffverfügbarkeit reagierten, während die Gruppe der Phenolglucoside nur geringe Schwankungen zeigte. Die Ergebnisse aller Versuchsfragen spiegeln das Spannungsfeld von landwirtschaftlichem Ertrag und pharmazeutisch geforderter Qualität wider, die häufig negativ korreliert sind. Bei der Produktion der Droge von Echter Goldrute muß daher eine Balance zwischen beiden Zielgrößen gefunden werden. / The aim of the presented studies was to evaluate the potential for cultivation of the European Goldenrod (Solidago virgaurea L.) and to examine the influences of harvesting date, cutting height, fertilization and of the abiotic environmental factors light and water on drug yield and compound content of the plant. In four field trials a fingerprint of 10 constituents, several parameters of drug yield, development stages and morphological traits were examined. The contents of flavonol glycosides, phenolic glucosides and caffeic acid derivatives were determined by HPLC and UV-detection by DAD. 45 european accession were sorted by their dates of anthesis and subdivided into the subspecies virgaurea and minuta and thereafter characterized by 33 morphological traits. The analysis of 452 individual plants showed ranges of 0.4 to 2.4 % flavonol glycosides, 0.7 to 4.6 % caffeic acid derivatives and 0.0 to 1.6 % phenolic glucosides. Within the examined accessions, especially subspecies virgaurea, a high variability of the phytochemical composition was observed. In an evaluation, accessions of subspecies virgaurea turned out to be most suitable for cultivation due to high drug yields up to 106 dt per ha and well-balanced spectra of constituents. During ontogenesis the drug yield of S. virgaurea increased, while compound contents varied (caffeic acid derivatives, flavonol glycosides) or decreased continuously (phenolic glucosides). Therefore a harvest aiming at high compound contents has to be carried out at a early development stage of mid budding. High mass and constituent yields can be obtained by a harvesting method with low cutting heights of 15 to 30 cm above ground. Plants in a sunny environment accumulated significantly higher amounts of flavonol glycosides and caffeic acid derivatives than shaded plants, which can be explained by the UV-protective function of these compound groups. Therefore it can be concluded that phytochemical variations during ontogenesis could be modified by different light conditions. Beside the expected drug yield increase, fertilization with nitrogen caused differences in the compound contents. The highest flavonol glycosides contents were observed in the unfertilized treatment, followed by treatments with organic fertilization, multinutrient fertilizer and calcium ammonium nitrate. While the nitrogen uptake by the plant (maximal 96 kg/ha N) and phosphorus (maximal 39 kg/ha P2O5) were relatively low, contrary potassium uptake (maximal 172 kg/ha K2O) was relatively high compared to other herbal drugs. In an overview of all influences it became obvious that the reaction of flavonol glycosides and caffeic acid derivatives were relatively sensitive to environmental influences such as light conditions and nutrient availability, while the group of phenolic glucosides showed low variations. The results of all field trials reflect the conflict between agricultural yield and pharmaceutical quality which are frequently negatively correlated. Therefore a balance between these two goals has to be found during drug production of S. virgaurea.
23

Uso de lâmpadas de diodo emissor de luz ‘LED’ no controle do florescimento em plantas de Tango (Solidago canadensis L.) e Hipérico (Hypericum inodorum) / The use of ‘LED’ light emitting diode to control the flowering of goldenrod (Solidago canadensis L.) and Hypericum (Hypericum inodorum) plants

Assis, Thamyres Reis de 06 November 2015 (has links)
Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2016-04-13T16:07:49Z No. of bitstreams: 1 texto completo.pdf: 1077166 bytes, checksum: 25fd76740634a7f9c6ac4a518a021ada (MD5) / Made available in DSpace on 2016-04-13T16:07:49Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1077166 bytes, checksum: 25fd76740634a7f9c6ac4a518a021ada (MD5) Previous issue date: 2015-11-06 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Diversos fatores podem afetar o crescimento e desenvolvimento das plantas. O fotoperíodo é um deles, sendo determinante para o controle do florescimento em plantas sensíveis. No campo, o controle é feito de forma artificial, para que as plantas floresçam durante todo o ano, independente do comprimento do dia. As lâmpadas incandescentes possuem seu uso difundido, porém, essas são pouco eficientes em converter energia elétrica em energia luminosa. O LED é uma tecnologia que surgiu na década de oitenta e possui grande potencial para ser utilizado na agricultura. Apresenta diversas vantagens como alta durabilidade, tamanho reduzido, baixa emissão de calor e eficiência em conversão de energia elétrica em luminosa. Devido ao pouco conhecimento sobre o impacto que a tecnologia do LED pode ter na agricultura, esta pesquisa visou elucidar o comportamento de duas espécies sensíveis ao fotoperíodo quando iluminadas por lâmpadas de LED. O primeiro estudo foi desenvolvido com o tango (Solidago canadensis L.), uma planta classificada como planta de dia curto, utilizada como flor de corte. Esse estudo objetivou avaliar o comportamento da produção de plantas de tango utilizando lâmpadas de LED para o controle do florescimento. Além disso, vislumbrou-se determinar o menor período de luz/escuro para o controle eficiente do florescimento. Para isso instalou-se um experimento em delineamento inteiramente casualizado, com quatro repetições. Foram utilizadas lâmpadas de LED na potência de 18 W, e foram avaliados quatro ciclos, que consistiram na alteração de períodos de luz e escuro expresso em minutos: 7/23; 15/15; 23/7 e 30/0. Os ciclos foram fornecidos das 22h às 2h, por um período de setenta dias. As testemunhas foram compostas por plantas sem iluminação suplementar e iluminadas com lâmpadas incandescentes de 100 W. A colheita ocorreu quando as hastes apresentaram cerca de 40% das inflorescências abertas. O segundo experimento foi conduzido com o hipérico (Hypericum inodorum), classificada como planta de dia longo facultativo, cuja principal utilização ornamental ocorre na fase de frutificação. Este trabalho foi realizado com o propósito de avaliar o efeito da iluminação artificial com lâmpada de LED de 18 W e incandescente de 100 W no controle do florescimento em plantas de hipérico em diferentes distâncias da projeção da lâmpada. As mudas foram cultivadas em cinco distâncias em relação à projeção horizontal da lâmpada: 0 m; 0,5 m; 1,0 m; 1,5 m e 2,0 m. Após o estabelecimento das plantas, realizou- se poda a vinte centímetros de altura. A iluminação artificial foi fornecida das 22h às 2h. Foram utilizados dois tipos de lâmpada: LED 18 W e incandescente de 100 W. Para que não houvesse interferência entre os tratamentos, efetuou- se o isolamento entre eles através do uso de lonas pretas. O uso da iluminação suplementar com lâmpadas de LED foi eficiente no controle fotoperiódico para as duas espécies estudas. Plantas de tango cultivadas sobre o ciclo de 7/23 minutos apresentaram menor tempo de cultivo e maior formação de ramos florais e conjunto de inflorescências. Porém os ciclos de 23/7 e 30/0 minutos foram aqueles que apresentaram os resultados mais expressivos nas características utilizadas para a classificação comercial, como tamanho e peso da haste. As plantas cultivadas sem suplementação completar não apresentaram formação de haste floral. Já nas iluminadas com lâmpadas de LED observou-se a diminuição do controle fotoperiódico com o aumento da distância. É necessário que as plantas de hipérico sejam expostas a dias curtos no início do cultivo para que as hastes atinjam o comprimento ótimo para a comercialização. / Several factors can affect the growth and development of plants. Photoperiod is a determining factor for flowering control in sensitive plants. In the field, control is done artificially, so that, plants flower throughout the year, regardless of day length. Incandescent lamps have widespread use, but they are less efficient in converting electrical energy into luminous energy. LED is a technology that emerged in the eighties and has great potential for use in agriculture. It has several advantages, such as high durability, small size, low heat emission and efficiency of electric energy conversion into light. Due to the little knowledge about the impact LED technology can have in agriculture, this research was carried out to elucidat the behavior of two species sensitive to photoperiod when lit by LED. The first study was developed with goldenrod (Solidago canadensis L.), classified as a short-day plant and used as a cut flower. This study aimed at evaluating the behavior of goldenrod production plants using LED lamps to control flowering. In addition, it seeked to determine the shortest period of light/dark for efficient control of flowering. For that purpose an experiment was carried out in a completely randomized design with four replications. In this test 18 W LED lamp were used, and four cycles of light/darkness were tested: 7/23'; 15/15'; 23/7'and 30/0'. The cycles were provided from 10pm to 2am, for a period of seventy days. The witnesses consisted of plants without supplemental lighting and illuminated with incandescent 100 W bulbs. Harvest occurred when the stems had about 40% of the inflorescence open. The second experiment was conducted with hypericum (Hypericum inodorum), classified as a facultative long-day plant and whose ornamental use occurs in the fruiting stage. This work was performed in order to evaluate the effect of artificial lighting with LED and incandescent bulbs targeting the flowering control in hypericum plants at different distances. The seedlings were placed in five distances in the horizontal projection oh the lamps: 0 m; 0.5 m; 1.0 m; 1.5 m and 2.0 m. After the establishment of plants, they were prunned down to twenty centimeters high. Artificial lighting was provided from 10pm to 2am. Two types of lamp were used: LED 18 W and incandescent 100 W. To avoid interference across treatments isolation with the use of black plastic was performed. The use of supplemental lighting with LED lamps was efficient in photoperiodic control for the two studied species. Goldenrod plants grown under the 7/23' cycle showed shorter cultivation period and increased formation of floral branches and number of inflorescences. However, the cycles of 23/7 "and 30/0" showed the most significant results in the characteristics used for commercial classification. Plants grown without light supplementation don’t formed the floral stems. Hypericum plants lit by incandescent lamps yielded similar production to those illuminated with LED lamps. In plants illuminated with LED lamps there was a decrease in the photoperiodic control as distance increase. Hypericum plants should be exposed to short days at the start of crop, so that the stems reach optimum length for sale.
24

Host-Associated Differentiation in an Insect Community

Dickey, Aaron 2010 December 1900 (has links)
Host-Associated Differentiation (HAD) is the formation of genetically divergent hostassociated lineages maintained by ecological isolation. HAD is potentially an important route to ecological speciation in parasites including many insects. While HAD case studies are accumulating, there is a dearth of negative results in the literature making it difficult to know how common the phenomenon really is or whether there are specific traits of parasites which promote HAD. To address these two problems, studies are needed which both publish negative results (i.e., parasites not showing HAD) and test for HAD in multiple parasite species on the same pair of host species (i.e., control for host plant effects). In this study, HAD was tested in three species of herbivorous insects and one parasitoid species on the same two host tree species: pecan and water hickory. The insects were selected based on the presence or absence of two traits, parthenogenesis and endophagy. A test for HAD was considered “positive” when population substructure was explained by host-association. To test for the presence of HAD, insects were sampled sympatrically to eliminate geographical isolation as a confounding factor, sampling was replicated spatially to assure that HAD persisted, and multiple loci were sampled from each individual. Genetic data was analyzed using cluster analyses. HAD was found in both pecan leaf phylloxera and yellow pecan aphid but not in pecan bud moth or in the parasitoid of the yellow pecan aphid, Aphelinus perpallidus. Interestingly, both taxa showing HAD are parthenogenetic and both taxa not showing HAD reproduce sexually. Species showing HAD were tested for the presence of a pre-mating reproductive isolating mechanism (RIM) which could be maintaining HAD despite the potential for gene flow. Selection against migrants to the alternative host was tested in yellow pecan aphid using a no-choice fitness experiment. The overall contribution of this RIM to total isolation was positive and ranged from 0.614 to 0.850. The RIM of “habitat preference” was tested in pecan leaf phylloxera using a dual-choice preference experiment. In this species, preference was only detected for phylloxera originating from water hickory suggesting that host discrimination ability may be a less important factor promoting differentiation in phylloxera.
25

Établissement de couverts végétaux visant à inhiber la germination, la croissance et la survie de la Berce du Caucase (Heracleum mantegazzianum)

Teasdale, Valérie 01 1900 (has links)
La berce du Caucase (Heracleum mantegazzianum) est une espèce envahissante provoquant des photodermatites lors d’un contact avec la sève. Son éradication laisse le sol à nu, facilitant ainsi sa réinfestation. L’objectif de mon projet est d’évaluer l’effet de l’ensemencement d’un couvert végétal pour empêcher l’établissement de la berce par phénomène de compétition. J’ai d’abord effectué une expérience en mésocosme utilisant cinq mélanges d’espèces herbacées afin de tester l’effet de la composition sur la germination, la croissance et la survie de la berce du Caucase. Trois mélanges, incluant ceux contenant Solidago canadensis, ont réduit le nombre de semences ayant germé. Tous les mélanges ont réduit la croissance et la survie des semis. Afin de déterminer si l’allélopathie pouvait être le mécanisme responsable de ce phénomène, j’ai testé l’effet de substances allélopathiques, extraites des feuilles et des racines du S. canadensis, sur la germination des semences de la berce. Bien qu’elle montre un effet allélopathique sur une espèce modèle (le radis), mon expérience n’a pas permis de détecter d’effet négatif sur la germination de la berce. Étant donné que celle-ci peut se faire dans l’obscurité, un mécanisme autre que la lumière ou l’allélopathie serait la cause de la réduction du taux de germination chez certains mélanges. Par contre, la réduction de la lumière par le couvert végétal serait la cause probable de la diminution de croissance et de la survie des semis. En définitive, un mélange composé majoritairement de graminées et produisant rapidement un couvert végétal dense aurait un meilleur potentiel pour la restauration suite à des travaux de lutte. / Giant Hogweed (Heracleum mantegazzianum) is an invasive species that causes human skin photodermatitis after contact with the sap. Control techniques of the plant often produced a soil devoid of vegetation cover, which facilitates reinvasion. The objective of my project was to evaluate the effect (competition) of plant seeding on the establishment of Giant Hogweed. First, I conducted a mesocosm experiment using five herbaceous plant mixtures in order to test the effect of composition and associated cover on germination, growth and survival of Giant Hogweed. Three mixtures, especially those with Solidago canadensis, reduced germination rate. Every mixture reduced growth and survival of Giant Hogweed seedlings. In order to identify the mechanism responsible for this phenomenon, I tested the effect of allelopathic substances, extracted from leaves and roots of S. canadensis, on germination of Giant Hogweed seeds. Although an allelopathic effect on a model species (radish) was detected, the substances did not impede Giant Hogweed germination. Considering germination occurs in darkness, a mechanism other than light or allelopathy would be responsible for the reduction of germination rate in certain plant mixtures. However, the reduction of light through plant cover would likely be the cause for the decrease of growth and survival of Giant Hogweed seedlings. A seed mixture mostly composed of grasses and rapidly producing a dense plant cover has a good potential for restoration following weeding.
26

Utbredning av den invasiva arten kanadensiskt gullris (Solidago canadensis) i Värmlands län, Sverige : Kan utbredning kopplas till viss typ av markanvändning eller markfuktighet? / Distribution of the invasive species Canadian goldenrod (Solidago canadensis) in Värmland county, Sweden : Can the distribution be linked to certain types of land use or soil moisture?

Ström, Alicia January 2023 (has links)
Invasive alien species (IAS) pose a serious threat to global ecosystems, economy and human and animal health. The spread of IAS leads to a global depletion of biological diversity, through homogenization of landscapes and reduced genetic variation within species. Canadian goldenrod (Solidago canadensis L.) is an IAS that occurs widely throughout most of Sweden and it is considered to be one of the country’s most problematic terrestrial IAS. The purpose of this study was to investigate the occurrence of the Canadian goldenrod in Värmland county, Sweden, in relation to land use type and soil moisture category. Species observation data was retrieved from the Analysis Portal for Biodiversity Data. National Land Cover Database (NMD) and SLU Soil Moisture Map were used to investigate which land cover and soil moisture classes Canadian goldenrod had been associated with. Results of this study shows that there is an association between Canadian goldenrod occurrence and land cover class, which implies that land cover seems to have an effect on the spread of the species. The area of land cover classes within reported observations of Canadian goldenrod was not proportional to the area of respective land cover classes within Värmland county. Land cover classes such as other open land, artificial surfaces and forests were most commonly found within Canadian goldenrod observations. This indicates that this species occurs with higher frequency on other open land and artificial surfaces, which corresponds with the literature findings. Moreover, the area of certain soil moisture class within reported observations of Canadian goldenrod was not proportional to the area of respective soil moisture class within Värmland. Among soil moisture classes, mesic-dry soil was most commonly found within goldenrod observations. This did not confirm the hypothesis that Canadian goldenrod occurs more commonly on wet-moist soils. The literature shows that this species has a great ability to adapt to different environments. The outcome of this study suggests that Canadian goldenrod might prefer certain land use categories more or less affected by human activity. This is consistent with previous studies about abundance and spread of invasive species and indicates that human activity is an important factor contributing to the spreading of IAS. / Invasiva främmande arter (IAS) utgör ett allvarligt problem för globala ekosystem, ekonomi och människors och djurs hälsa. Spridningen av IAS leder till en global utarmning av biologisk mångfald, genom homogenisering av landskap och minskad genetisk variation inom arter. Kanadensiskt gullris (Solidago canadensis L.)  är en IAS som förekommer vitt spridd över så gott som hela Sverige och bedöms vara en av landets mest problematiska invasiva terrestra arter. I denna studie kartläggs utbredningen av kanadensiskt gullris i Värmlands län, i syfte att undersöka om utbredningen kan kopplas till viss typ av markanvändning eller markfuktighet. Artobservationsdata hämtades från Analysportalen för biodiversitetsdata. Nationella Marktäckedata (NMD) och SLU Markfuktighetskarta (klassad) användes för att undersöka vilka marktäcke- och markfuktighetsklasser kanadensiskt gullris associerats med. Studiens resultat talar för att det finns ett samband mellan förekomst av kanadensiskt gullris och marktäckeklasser, dvs. marktäckning verkar påverka utbredning. Arean av marktäckeklasser inom rapporterade observationer av kanadensiskt gullris var inte proportionell till arean för respektive marktäckeklasser inom Värmlands län. Marktäckeklasserna övrig öppen mark, exploaterad mark och skog var vanligast förekommande inom kanadensiskt gullrisobservationer. I studien indikeras att kanadensiskt gullris oftare förekommer inom klasserna övrig öppen mark och exploaterad mark, vilket överensstämmer med litteraturen. Dessutom var arean av viss markfuktighetsklass inom rapporterade observationer av kanadensiskt gullris inte proportionell till arean av respektive markfuktighetsklass inom Värmland. Bland markfuktighetsklasser var torr-frisk vanligast inom kanadensiskt gullrisobservationer. Detta bekräftade inte hypotesen att kanadensiskt gullris har en högre förekomst inom klassen fuktig-blöt, men stöds av litteraturen som talar om artens anpassningsförmåga till olika fuktighetsnivåer. Resultatet av denna studie tyder på att kanadensiskt gullris verkar föredra platser som mer eller mindre påverkas av mänsklig aktivitet, något som går i linje med tidigare studier gällande spridning och förekomst av invasiva arter och lyfter vikten av den mänskliga faktorns betydelse i spridningen av IAS.

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